Medicare RAC Overpayment Redetermination Appeal

The situation

Dr. Okafor's three-provider family practice gets a letter from Cotiviti, the new RAC contractor for her region: a sample of 30 claims was reviewed, 9 were found non-compliant, and the finding was extrapolated across all similar claims from the past 3 years, a $180,000 recoupment demand. She has 15 days to informally rebut it. Her billing staff has never dealt with an extrapolated finding before and doesn't know that the extrapolation methodology itself is often the strongest thing to challenge.

Who receives this

Small physician and provider practices (1-10 providers) that receive a Medicare RAC overpayment finding, especially one based on statistical extrapolation from a claim sample.

Why the agency will not advise you

RAC contractors are paid on contingency from what they recover, giving them zero incentive to help a practice successfully rebut a finding; specialty societies stick to general education rather than practice-specific tools, and generic appeal-letter generators don't know what an extrapolation-methodology challenge even is.

Key facts, with sources

• CMS's Recovery Audit Contractor program identifies Medicare Fee-for-Service overpayments; on April 28, 2025, CMS awarded Cotiviti GOV Services LLC the RAC contracts for Regions 3, 4, and 5, with the contractor anticipated to begin reviews in summer 2025, a contractor transition that resets audit priorities and creates fresh review volume. Providers have 15 days to informally rebut a finding to avoid automatic recoupment, then 120 days to file a formal Redetermination request using CMS Form 20027, contesting the coding, medical-necessity, or statistical-extrapolation basis of the finding. Source: Medicare Fee for Service Recovery Audit Program — CMS · First Level of Appeal: Redetermination by a Medicare Contractor — CMS · Recovery Audit Contractor (RAC) FAQ — ACEP
• Available self-serve resources for RAC-adjacent appeals are generic insurance appeal letter generators built for commercial-payer medical-necessity denials (River Editor's AI appeal letter generator, RCM Tools' free insurance appeal letter generator, Austenriggs's downloadable templates), not tools built for the RAC program's distinct arguments, particularly statistical-extrapolation-methodology challenges, a technical argument most small practices don't know is available to them. Specialty medical societies provide educational FAQ content, and Medicare audit defense attorneys provide paid representation, but no self-serve RAC redetermination-package generator was found. Source: Free AI Insurance Appeal Letter Generator — River · Medicare Audit Defense Attorneys | RAC, MAC, UPIC & CMS Audits

When to bring in a professional

Self-serve responses fit routine cases: clear facts, amounts a business can absorb, and a deadline still ahead of you. Bring in a licensed professional when the amount at stake is large relative to their fee, the facts are genuinely disputed, criminal exposure is possible, or the deadline has already passed. A short paid consultation to sanity-check your plan is often worth it even when you handle the filing yourself.

All sources for this guide

1. Medicare Fee for Service Recovery Audit Program — CMS
2. First Level of Appeal: Redetermination by a Medicare Contractor — CMS
3. Recovery Audit Contractor (RAC) FAQ — ACEP
4. Free AI Insurance Appeal Letter Generator — River
5. Medicare Audit Defense Attorneys | RAC, MAC, UPIC & CMS Audits